The good news is curbing methane emitting industries can make a huge difference, according to researchers

Maybe cutting down on man-caused methane emissions can make a difference.

Studying air trapped inside ice cores drilled in Greenland, a research team that includes an Oregon State researcher have found evidence that the global fossil fuel industry emits 25 to 40 percent more methane than previously thought. Methane is a greenhouse gas and large contributor to global warming. The study was published in Nature Feb. 19.

To uncover this evidence, researchers traveled to the interior of the Greenland ice sheet and drilled ice core samples. The samples contain bubbles of air from the pre-industrial period, around the 1750s. The study then measured the changes of from the early 18th century to the present day.

Christo Buizert, the researcher from Oregon State, says in a statement that the ice core samples measured are the largest ever, making the study a “Herculean effort.”

The researchers found that the early samples had methane from natural sources until 1870, which is coincides with the sharp increase in the use of fossil fuels. Present day man-caused methane comes from extraction of fossil fuels and natural gas leaks from pipelines, factories and homes.

Because the levels of naturally sourced methane were about 10 percent below what it was previously reported, the researchers deduced that man-caused fossil fuel emissions are much higher. Although carbon dioxide takes thousands of years to remove from the climate system and is the largest contribution to global warming, methane has more of an impact despite its short life. Its average lifetime in the atmosphere is nine years, the authors said in the study.

The good news of this study is that it’s evidence showing cutting down on human caused greenhouse gas emissions could make a difference, they add.

“If we stopped emitting all carbon dioxide today, high carbon dioxide levels in the atmosphere would still persist for a long time,” says one of the researchers from University of Rochester, Benjamin Hmiel. “Methane is important to study because if we make changes to our current methane emissions, it’s going to have an impact more quickly.”

Reducing emissions from human activities, like fossil fuel extraction, could have an impact in curbing future global warming, the researchers say.

“By better understanding the sources of methane to the atmosphere, we can implement more targeted reduction strategies going forward,” Buizert says.

The published study comes at a moment as the Oregon Legislature is trying to pass climate action legislation, a cap and trade policy. At the time of this posting, SB 1530 is in committee and Senate Republicans are still threatening to walk out. For some Republicans, they want voters to decide the fate of the policy. If the legislative short session ends without climate action legislation, Renew Oregon is in the process of putting three climate action measures to the ballot in November.

Discovering that more methane is man-caused means policies that cut down on greenhouse gas emissions will make a big difference in curbing global warming, according to Hmiel.